Will Unionism Prosper in Cyber-Space? The Promise of the Internet for Employee Organization

This paper argues that the low cost of information, communication, and interaction on the Web offers trade unions opportunities to improve services and attract members and thus reinvent themselves for the 21st Century. Analyzing current use of the Internet by unions in the United Kingdom and United States, we develop five hypothesis about the impact of the Internet on unions. 1) the Customized Services hypothesis that unions will individualize services; 2) the Cyber-organizing hypothesis that the Web will ease organization and produce virtual minority unions at many non-union firms; 3) the Cyber-democracy hypothesis that the Web will enhance democracy in unions; 4) the Cyber-dispute hypothesis that the Web will become an important space for industrial disputes; and 5) the New Internationalism hypothesis that the Web will strengthen the international labor community. If unions fail to exploit the opportunities on the Web to gain members, we expect other organizations, Internet recruitment sites, specialized advice centers, and the like, to fill the e-union niche.

First Canadian Record of \u3ci\u3eHexacola Neoscatellae\u3c/i\u3e (Hymenoptera: Figitidae: Eucoilinae), A Parasitoid of the Shore Fly, \u3ci\u3eScatella Stagnalis\u3c/i\u3e

This paper documents the first occurrence of Hexacola neoscatellae, a shore fly parasitoid, in Canada. The discovery of H. neoscatellae is significant because currently there are no suitable biological control agents available for shore fly control to the floriculture industry

Stimuli-controlled movement of droplets and polymeric “vehicles”

Stimuli-responsive materials have gained much attention recently as new means for fluid flow control within the field of microfluidics. The ability to control of droplets and polymeric “vehicles” in a contactless manner within microfluidic chips offers new and exciting possibilities such as directed transport of molecular cargo to desired destinations and dynamic sensing of the fluidic environment during movement

Chemotactic movement of ionic liquid droplets

Chemotactic movement of ionic liquid droplets Herein we report the chemotactic behaviour of self-propelled droplets composed solely of the ionic liquid (IL) trihexyl(tetradecyl)phosphonium chloride ([P6,6,6,14][Cl]). These droplets move spontaneously across the liquid/interface and are guided to specific destinations within open fluidic channels through the use of chloride gradients. The movement of these droplets is controlled by the triggered release of the [P6,6,6,14] + cation, a component of the IL and a very efficient cationic surfactant. Surfactant release has been previously used to develop smart droplets which can solve complex mazes [1] or can be photo-manipulated [2]. In this study the [P6,6,6,14]+ diffuses from the droplet into the aqueous solution which causes a local drop in surface tension, this creates marangoni like flows which drive the droplet from areas of low surface tension to high surface tension. The rate of [P6,6,6,14]+ release depends on the concentration of the chloride in the aqueous solution, as the formation of free [P6,6,6,14]+ (the active surfactant at the air-aqueous interface) through dissociation of the relatively closely associated [P6,6,6,14][Cl] ions in the IL depends on the local Cl- concentration at the IL-aqueous boundary. We envision that these smart IL droplets could be used for a variety of applications within the microfluidic sector such as dynamic sensing, cargo transport and serve as micro-vessels for chemical reactions. Furthermore we believe this new approach to micro-vehicle movement will provide a much broader base for the development of a wide range of new droplet chemistries that exploit the vast and still rapidly growing numbers of ionic liquids. [1] I. Lagzi, S. Soh, P. Wesson, K. Browne and B. Grzybowski, Journal of the American Chemical Society, 2010, 132, 1198-1199. [2] L. Florea, K. Wagner, P. Wagner, G. G. Wallace, F. Benito‐Lopez, D. L. Officer and D. Diamond, Advanced materials, 2014

Stimuli-controlled fluid movement at the microscale

The integration of stimuli-responsive materials into microfluidic system provides external control over fluid flow and can reduce the over-all complexity of the microfluidic device [1, 2]. In this work, we present two main approaches for stimuli-controlled fluid movement at the microscale. The first approach comprises the use of photo-actuated hydrogels as micro-valves, while the second approach involves stimuli-controlled movement of synthetic micrometre size droplets. 1. Photo-actuator hydrogels were developed using copolymers of N-isopropylacrylamide, acrylated spiropyran and acrylic acid. In water, the acrylic acid comonomer dissociates, resulting in the protonation of the photochromic spiropyran (SP) to protonated merocyanine (MC-H+). This form is hydrophilic, allowing the hydrogel to swell. Exposure to white light promotes isomerisation of the MC-H+ form to the hydrophobic SP form, which triggers contraction of the hydrogel. In this manner, reversible photo-control over the volume of the hydrogel was achieved. It was found that different polymerization solvents directly influenced the morphology of the resulting hydrogels, and in particular, the porosity. This in turn influences the diffusion pathlength of water into/out of the gel, which has a dramatic impact on the swelling and shrinking kinetics of the hydrogel. Microstructures composed of optimised hydrogels were photopolymerised within microfluidic channels, and their application as photo-controlled valves demonstrated. These photo actuators are of great interest as they can be controlled using light, in a noncontact manner. They are also of great interest for biological applications as they can operate in neutral solutions, in contrast to previous formulations [3]. 2. For the second approach, micrometre size droplets were designed to move in an open fluidic channel. The motion of these discrete droplets was controlled by the triggered release of surfactant molecules, which were contained within the droplet. Once released, the surfactant altered the surface tension of the aqueous phase. As the solubility of the droplet-contained surfactant varied with the pH of the aqueous solution, these droplets were guided to specific destinations in fluidic channels through the use of pH gradients. These gradients can be created on demand within microfluidic channels using light due to the photoconversion of sulphonated (water soluble) MC-H+ to SP. This increases the local acidity due to the release of free protons from MC-H+, which triggers the release of surfactant, and stimulates the photo-controlled movement of the droplets

Thermo and salt responsive poly(ionic liquid)s.

Poly(ionic liquid)s are defined as ionic liquids which feature polymerizable groups in either the cation, the anion, or both. The aim of this study is to synthesize a tributylhexyl phosphonium sulfopropyl acrylate (PSPA) poly(ionic liquid) (PIL) hydrogel and characterise its temperature and salt concentration induced shrinking. The gels were polymerised in circular moulds and were hydrated in deionized water (DI water). The percent shrinking upon exposure to a stimulus was calculated using the formula: %s = (Ai- Af)/Ai x 100, where Ai is the initial area of the swollen hydrogel and Af is the final area of the hydrogel after the application of the stimulus

Stimuli-controlled manipulation of synthetic micrometre-sized “vehicles” for bio-inspired fluidics

Controlled movement in fluids is essential to the function of living systems. The desire of [...

Self-propelled chemotactic ionic liquid droplets

Herein we report the chemotactic behaviour of self-propelled droplets composed solely of the ionic liquid trihexyl(tetradecyl)phosphonium chloride ([P6,6,6,14][Cl]). These droplets spontaneously move along an aqueous-air boundary in the direction of chloride gradients to specific destinations due to asymmetric release of [P6,6,6,14]+ cationic surfactant from the droplet into the aqueous phase

Self-propelled chemotactic droplets

The ability to move in response to an external stimulus is essential for many lifeforms. Certain cells such as bacteria, somatic cells, and other single cell or multicellular organisms move in response to chemical stimuli present in their environment. This phenomenon, known as chemotaxis, is crucial for many biological processes. Notably there are only few equivalents of similar chemotactic-driven “micro-vehicles” in the synthetic world